Police cracked the crime after a 13-hour-long questioning of Soumya, 28.
Soumya was taken for questioning when she was convalescing at a state run hospital near Kannur after being admitted for nausea and indigestion - incidentally the same symptoms that her parents and her elder daughter suffered before they died.
While her mother died on March 7, her father on April 13, her daughter died on January 31. However, following a complaint from a relative, the body of the child was exhumed after rat poison was found in the viscera of her parents.
Incidentally this incident happened in the home village of Chief Minister Pinarayi Vijayan and it was only after his intervention did the police speeden their investigation.
The woman was separated from her husband and according to police, her motive was that her parents and child were "impediments to her wayward life".
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